View source for U-43-class submarine (Austria-Hungary)

{{Short description|Austro-Hungarian Navy submarines during WWI}}
{{Hatnote|For other ship classes of the same name, see [[U-43-class submarine (disambiguation)|U-43-class submarine]]}}
{|{{Infobox ship begin}}
{{Infobox ship image
|Ship image=[[File:German submarine SM UB-43.jpg|300px|{{SMU|U-43|Austria-Hungary|6}} in port, c. 1915–16, while still in the [[German Imperial Navy]] (as ''UB-43'')]]
|Ship caption={{SMU|U-43|Austria-Hungary|6}} in port, c. 1915–16, while still in the [[German Imperial Navy]] (as ''UB-43'')
}}
{{Infobox ship class overview
|Builders=[[AG Weser]], [[Bremen]]<ref name=Con-344>Gardiner, p. 344.</ref>
|Operators={{navy|Austria-Hungary}}
|Class before=[[U-27 class submarine (Austria-Hungary)|''U-27''-class submarine]]
|Class after={{sclass|U-48|submarine|1}}
|Built range=1916
|In commission range=1917–1918
|Total ships completed=2
|Total ships lost=0
|Total ships scrapped=2
|Total ships preserved=0
}}
{{Infobox ship characteristics
|Hide header=
|Header caption=
|Ship type=[[submarine]]
|Ship displacement=*{{convert|263|MT|ST|abbr=on}} surfaced
*{{convert|292|MT|ST|abbr=on}} submerged<ref name=Con-344 />
|Ship length={{convert|118|ft|5|in|m|abbr=on}}<ref name=Con-344 />
|Ship beam={{convert|14|ft|4|in|m|abbr=on}}<ref name=Con-344 />
|Ship draft={{convert|12|ft|2|in|m|abbr=on}}<ref name=Con-344 />
|Ship propulsion=*2 × shaft
*2 × [[diesel engine]], {{convert|284|bhp|abbr=on}} total
*2 × [[electric motor]], {{convert|280|shp|abbr=on}} total<ref name=Con-344 />
|Ship speed=*{{convert|9.2|knots|km/h}} surfaced
*{{convert|5.8|knots|km/h|0}} submerged<ref name=Con-344 />
|Ship range=
|Ship endurance=
|Ship test depth=
|Ship complement=22<ref name=Con-344 />
|Ship armament=*2 × {{convert|50|cm|in|1|abbr=on}} bow torpedo tubes; 4 torpedoes
*1 × 88 mm/26 (3.5 in) [[deck gun]]
*1 × {{convert|8|mm|in|abbr=on}} [[machine gun]]<ref name=Con-344 />
|Ship notes=
}}
|}
The '''''U-43'' class''' was a [[ship class|class]] of two [[coastal submarine]]s or [[U-boats]] operated by the [[Austro-Hungarian Navy]] ({{langx|de|Kaiserliche und Königliche Kriegsmarine}} or {{lang|de|K.u.K. Kriegsmarine}}) during [[World War I]]. The two [[submarine]]s that comprised the class were [[German Type UB II submarine|Type UB II submarines]] of the [[Imperial German Navy]], making the two classes identical. From the beginning of World War I, Austria-Hungary had been working to increase the size of its U-boat fleet, so the Imperial German Navy, which was finding it difficult to obtain trained submarine crews, sold two of its UB II boats, {{SMU|UB-43||2}} and {{SMU|UB-47||2}}, to its ally in June 1917.

The German Type UB II design incorporated improvements over [[German Type UB I submarine|Type UB I]] boats, the first coastal submarines of the German Imperial Navy. Among these were twin engines and shafts for more redundancy during operations, a higher top speed, and larger torpedo tubes with double the complement of torpedoes. As a result, the UB II boats were nearly twice as heavy as their predecessor UB I boats.

Both boats of the class were selected for German service in the Mediterranean while under construction. They were shipped via rail to [[Pula|Pola]], assembled, [[launch (ship)|launch]]ed, and [[commission (ship)|commission]]ed in the German Imperial Navy, where both enjoyed great success against Allied shipping. In June 1917, the boats were decommissioned, handed over to Austria-Hungary, and then commissioned into the Austro-Hungarian Navy in July. The ''B'' in the designation of both boats was dropped, but the submarines retained the same numbers, becoming ''U-43'' and ''U-47'' under the Austro-Hungarian flag. At the end of the war {{SMU|U-43|Austria-Hungary|2}} and {{SMU|U-47|Austria-Hungary|2}} were ceded to Italy and France, respectively, and had been scrapped by 1920.

== Background ==
[[Austria-Hungary]]'s U-boat fleet was largely obsolete at the outbreak of [[World War I]].<ref name=Con-341>Gardiner, p. 341.</ref> The [[Austro-Hungarian Navy]] satisfied its most urgent needs by purchasing five [[German Type UB I submarine|Type UB I]] submarines that comprised the {{sclass|U-10|submarine|4}} from Germany,<ref name=Con-343>Gardiner, p. 343.</ref> by raising and recommissioning the sunken French submarine [[French submarine Curie (Q 87)|''Curie'']] as {{SMU|U-14|Austria-Hungary|2}},<ref name=Con-341 /><ref group=Note>[[French submarine Curie (Q 87)|''Curie'']] had been caught in an [[anti-submarine net]] while trying to enter the harbor at [[Pula|Pola]] on 20 December 1914. See: Gardiner, p. 343.</ref> and by building four submarines of the {{sclass|U-20|submarine|4}} that were based on the 1911 Danish [[Havmanden class submarine (1911)|''Havmanden'' class]].<ref name=Con-344 /><ref group=Note>The plans for the Danish [[Havmanden class submarine (1911)|''Havmanden'' class submarines]], three of which were built in Austria-Hungary, were seized from [[Whitehead & Co.]] in [[Fiume]]. See: Gardiner, pp. 344, 354.</ref>

After these steps alleviated the most urgent needs,<ref name=Con-341 /> the Austro-Hungarian Navy had adopted the German Type UB II design for what became known as the Austro-Hungarian [[U-27 class submarine (Austria-Hungary)|''U-27'' class]] in mid 1915, and had six of that class being built under license in Austria-Hungary by late 1916.<ref name=Hal-383 /><ref group=Note>A further two [[U-27 class submarine (Austria-Hungary)|''U-27'' class boats]] were started in 1916. See: Halpern, p. 383.</ref> In November 1916, Germany had inquired to find out if Austria-Hungary were interested in purchasing existing German submarines because Germany was having a hard time finding trained submarine crews. After protracted negotiations, which had stalled over the outflow of Austro-Hungarian gold reserves to Germany, an agreement to purchase two submarines—''UB-43'' and ''UB-47''—was reached in June 1917.<ref name=BS>Baumgartner and Sieche, as excerpted [http://www.gwpda.org/naval/ahsubs.htm here] (reprinted and translated into English by Sieche). Retrieved 2 December 2008.</ref>

== Design ==

===The UB II design ===
The German UB II design of coastal submarines was a development from the design of the UB I boats, which had been originally ordered in September 1914.<ref name=Con-174>Gardnier, p. 174.</ref><ref group=Note>The [[Austro-Hungarian Navy]]'s {{sclass|U-10|submarine|1}}s were German-built [[German Type UB I submarine|UB I boats]]. Two of the ''U-10'' class had, like the two ''U-43'' boats, been originally [[commission (ship)|commissioned]] into the [[Imperial German Navy]]. See: Gardiner, p. 343.</ref> During their trials, the UB I boats were found to be too small and too slow, but in-service use revealed another problem. The UB I boats had a single [[propeller shaft (ship)|propeller shaft]]/engine combo such that if either component failed, the U-boat became almost totally disabled.<ref name=Miller-48>Miller, p. 48.</ref> The UB II boats featured twin propeller shafts and twin engines (one shaft for each engine) which not only alleviated this problem, but also had the added benefit of increasing the top speed.<ref name=Will-13>Williamson, p. 13.</ref> The new design also included more powerful batteries,<ref name=Miller-48 /> larger torpedo tubes, and a [[deck gun]].<ref name=Tarrant-172>Tarrant, p. 172.</ref> The UB II boats could also carry twice the torpedo load of their predecessors, and nearly ten times as much fuel.<ref name=Tarrant-172 /> To contain all of these changes the [[submarine hull|hull]] was larger,<ref name=Miller-48 /> and the surface and submerged [[displacement (ship)|displacement]] was more than doubled.<ref name=Tarrant-172 />

The UB II boats were ordered from three manufacturers in groups that numbered between two and twelve. Each group had slight variations in design, resulting in differences in displacements, lengths, speeds, fuel capacities, and operational ranges.<ref name=Tarrant-172 />

=== The ''U-43''-class design ===
The ''U-43'' class consisted of two boats from a contracted group of six UB II boats built by [[AG Weser]] of [[Bremen]].<ref name=Tarrant-172 /><ref group=Note>The six boats were numbered sequentially from ''UB-42'' to ''UB-47''.</ref> Like all of the UB II boats from different manufacturers and contract groups, the ''U-43'' group had distinct specifications. This group displaced {{convert|272|MT|ST}} surfaced and {{convert|305|MT|ST}} submerged.<ref name=Tarrant-172 /> The boats had a single [[submarine hull|hull]] with [[saddle tank (submarine)|saddle tank]]s (an early style of [[ballast tank]]s),<ref name=Con-181>Gardiner, p. 181.</ref> and were {{convert|121|ft|1|in|m}} long with a [[beam (nautical)|beam]] of {{convert|14|ft|4|in|m}} and a [[draft (hull)|draft]] of {{convert|12|ft|2|in|m}}.<ref name=Con-344 /> For propulsion, they featured two shafts, twin [[diesel engine]]s of {{convert|270|bhp|abbr=on}} for surface running, and twin [[electric motor]]s of {{convert|280|shp|abbr=on}} for submerged travel.<ref name=Con-344 /> The boats were capable of {{convert|8.8|knots|km/h|1}} while surfaced and {{convert|6.2|knots|km/h}} submerged. The range of the boats was {{convert|6940|nmi|km}} at {{convert|5|knots|km/h}} surfaced, and {{convert|45|nmi|km}} at {{convert|4|knots|km/h}} submerged.<ref name=Tarrant-172 /> The ''U-43'' class boats were designed for a crew of 22.<ref name=Con-344 />

The ''U-43'' class boats were armed with two {{convert|50|cm|in|1|abbr=on}} bow torpedo tubes and carried a complement of four torpedoes. They were each equipped with an 88&nbsp;mm/26 (3.5&nbsp;in) [[deck gun]] and an {{convert|8|mm|in|abbr=on}} [[machine gun]].<ref name=Con-344 />

The two ''U-43''-class U-boats were nearly identical to the eight boats of the Austro-Hungarian Navy's ''U-27'' class, which were built to UB II plans. Despite the similarities, the two groups are identified in sources as distinct classes.<ref name=Con-344 /><ref name=nh-net>{{cite web | last = Smith | first = Gordon | title = Austro-Hungarian Navy: Submarines | url = http://www.naval-history.net/WW1NavyAustrian.htm#ss | work = World War 1 at Sea | date = 15 September 2008 | access-date = 30 December 2008 }}</ref>

== Construction ==
The six-boat group that included ''UB-43'' and ''UB-47'' was ordered in July 1915,<ref name=autogenerated1>Tarrant, p. 161.</ref> and both boats had been [[keel laying|laid down]] in early September.<ref name=UB-43>{{cite web | last = Helgason | first = Guðmundur | title = WWI U-boats: UB-43 | url = http://uboat.net/wwi/boats/index.html?boat=UB+43 | work = U-Boat War in World War I | access-date = 2 December 2008 }}</ref><ref name=UB-47>{{cite web | last = Helgason | first = Guðmundur | title = WWI U-boats: UB-47 | url = http://uboat.net/wwi/boats/index.html?boat=UB+47 | work = U-Boat War in World War I | access-date = 2 December 2008 }}</ref> This group was selected by the German [[German Imperial Admiralty Staff|Admiralstab]] for deployment to the Mediterranean, but, unlike the smaller UB I boats, they could not as easily be transported overland by rail.<ref name=Hal-383>Halpern, p. 383.</ref> Weser prepared the boats for rail shipment by cutting the boat sections longitudinally,<ref name=Miller-49>Miller, p. 49.</ref> and sent all the materials, along with German shipyard workers, to [[Pula|Pola]], where the boats were reassembled.<ref name=Hal-383 /> ''UB-43'' was launched in early April 1916,<ref name=UB-43 /> while ''UB-47'' followed in June.<ref name=UB-47 />

== Class members ==

=== SM ''U-43'' ===
{{main|SM U-43 (Austria-Hungary)}}
''UB-43'' was ordered by the [[Imperial German Navy]] on 31 July 1915 and was [[keel laying|laid down]] by [[AG Weser]] of [[Bremen]] on 3 September.<ref name=UB-43 /> While under construction, she was one of a group of six U-boats selected for service in the Mediterranean.<ref name=Hal-383 /> ''UB-43'' was broken into railcar-sized components and shipped overland to the Austro-Hungarian port of [[Pula|Pola]] where Weser workers assembled her.<ref name=Hal-383 /><ref name=Miller-49 /> She was [[launch (ship)|launch]]ed on 8 April 1916 and [[commission (ship)|commission]]ed into the Imperial German Navy as SM ''UB-43'' on 24 April, under the command of ''[[Oberleutnant zur See]]'' Dietrich Niebuhr.<ref name=UB-43 /> ''[[Kapitänleutnant]]'' [[Hans-Joachim von Mellenthin|Hans von Mellenthin]] was assigned to the boat in late August 1916,<ref name=UB-43 /> and led the boat in sinking 19 ships ({{GRT|86,236}}) over the next 8½ months.<ref name=UB43-ships>{{cite web | last = Helgason | first = Guðmundur | title = Ships hit during WWI: Ships hit by UB-43 | url = http://uboat.net/wwi/ships_hit/search.php?boat=UB+43 | work = U-Boat War in World War I | access-date = 2 December 2008 }}</ref> In April 1917, von Mellenthin was replaced by ''Oberleutnant zur See'' Horst Obermüller who commanded the ship for the next three months,<ref name=UB-43 /> sinking three more ships ({{GRT|12,940}}) and damaging the British cruiser {{HMS|Grafton|1892|2}}.<ref name=UB43-ships /> ''UB-43'' was decommissioned on 15 July and taken over by the Austro-Hungarian Navy.<ref name=BS />

Renamed ''U-43'' for Austro-Hungarian service, the boat became the [[class leader]] of the ''U-43'' boats when she was commissioned into the Austro-Hungarian Navy on 30 July 1917.<ref name=KUK-U-43>{{cite web | last = Helgason | first = Guðmundur | title = WWI U-boats: U KUK U43 | url = http://uboat.net/wwi/boats/index.html?boat=KUK+U43 | work = U-Boat War in World War I | access-date = 2 December 2008 }}</ref> The submarine's successes while under German command were not matched under Austro-Hungarian; she damaged a single ship in November 1917 in her only successful attack.<ref name=U43-ships>{{cite web | last = Helgason | first = Guðmundur | title = Ships hit during WWI: Ships hit by KUK U43 | url = http://uboat.net/wwi/ships_hit/search.php?boat=KUK+U43 | work = U-Boat War in World War I | access-date = 2 December 2008 }}</ref> ''U-47'' was surrendered to France as a war reparation in 1920 and was broken up at [[Bizerta]].<ref name=Gib-388>Gibson and Prendergast, p. 388.</ref>

=== SM ''U-47'' ===
{{main|SM U-47 (Austria-Hungary)}}
''UB-47'' was ordered by the Imperial German Navy on 31 July 1915 and was laid down at Bremen by AG Weser on 4 September.<ref name=UB-47 /> As one of six U-boats selected for service in the Mediterranean while under construction, she was broken into railcar-sized components and shipped overland to the Austro-Hungarian port of [[Pula|Pola]].<ref name=Hal-383 /><ref name=Miller-49 /> Shipyard workers from Weser assembled the boat and her five sisters at Pola,<ref name=Hal-383 /> where she was launched on 17 June.<ref name=UB-47 />

SM ''UB-47'' was commissioned into the Imperial German Navy on 4 July 1916 under the command of ''Oberleutnant zur See'' [[Wolfgang Steinbauer]].<ref name=UB-47 /> Steinbauer and ''UB-47'' sank 15 ships ({{GRT|62,676}} and 11,100  tons) over the next nine months, including two [[Cunard Line]] steamers—{{RMS|Franconia|1910|2}} and {{SS|Ivernia||2}}—serving as British [[troopship]]s, as well as the French battleship {{ship|French battleship|Gaulois||2}}.<ref name=UB47-ships>{{cite web | last = Helgason | first = Guðmundur | title = Ships hit during WWI: Ships hit by UB-47 | url = http://uboat.net/wwi/ships_hit/search.php?boat=UB+47 | work = U-Boat War in World War I | access-date = 2 December 2008 }}</ref> Steinbauer also damaged three ships with a combined gross register tonnage of 16,967. Under the command of Hans Hermann Wendlandt, who had replaced Steinbauer in April 1917, ''UB-47'' sank an additional seven ships ({{GRT|13,519}} and 350 tons) through 21 July, at which time the ship was decommissioned and handed over to the Austro-Hungarian Navy.<ref name=BS /><ref name=UB47-ships />

The ''B'' in her designation was dropped when she was commissioned as SM ''U-47'' for the Austro-Hungarian Navy on 30 July 1917.<ref name=KUK-U-47>{{cite web | last = Helgason | first = Guðmundur | title = WWI U-boats: U KUK U47 | url = http://uboat.net/wwi/boats/index.html?boat=KUK+U47 | work = U-Boat War in World War I | access-date = 2 December 2008 }}</ref> ''U-47''{{'}}s success under Austro-Hungarian command was less than that under the German flag; only three ships ({{GRT|6,201}} and 351 tons) were sunk through the end of the war.<ref name=U47-ships>{{cite web | last = Helgason | first = Guðmundur | title = Ships hit during WWI: Ships hit by KUK U47 | url = http://uboat.net/wwi/ships_hit/search.php?boat=KUK+U47 | work = U-Boat War in World War I | access-date = 2 December 2008 }}</ref> ''U-47'' was surrendered to France as a war reparation in 1920 and was broken up at [[Bizerta]].<ref name=Gib-388 />

== Notes ==
{{Reflist|group=Note}}

== References ==
{{Reflist}}

== Bibliography ==
{{Refbegin}}
* {{cite book | last = Baumgartner | first = Lothar |author2=Erwin Sieche | title = Die Schiffe der k.(u.)k. Kriegsmarine im Bild = Austro-Hungarian warships in photographs | language = de | location = [[Vienna|Wien]] | publisher = Verlagsbuchhandlung Stöhr | year = 1999 | isbn = 978-3-901208-25-6 | oclc = 43596931 }}
* {{cite book | editor-last = Gardiner | editor-first = Robert | title = Conway's All the World's Fighting Ships 1906–1921 | location = [[Annapolis, Maryland]] | publisher = [[Naval Institute Press]] | year = 1985 | isbn = 978-0-87021-907-8 | oclc = 12119866 }}
* {{cite book | last1 = Gibson | first1 = R. H. | last2=Prendergast | first2=M. <!-- not the American painter --> | title = The German Submarine War, 1914–1918 | location = Annapolis, Maryland | publisher = Naval Institute Press | year = 2003 | orig-year = 1931 | isbn = 978-1-59114-314-7 | oclc = 52924732 }}
* {{cite book | last = Halpern | first = Paul G. | title = A Naval History of World War I | location = Annapolis, Maryland | publisher = Naval Institute Press | year = 1994 | isbn = 978-0-87021-266-6 | oclc = 28411665 }}
* {{cite book | last = Miller | first = David | title = The Illustrated Directory of Submarines of the World | location = [[St. Paul, Minnesota]] | publisher = MBI Pub. Co | year = 2002 | isbn = 978-0-7603-1345-9 | oclc = 50208951 }}
* {{cite book | last = Tarrant | first = V. E. | title = The U-Boat Offensive: 1914–1945 | location = Annapolis, Maryland | publisher = Naval Institute Press | year = 1989 | isbn = 978-0-87021-764-7 | oclc = 20338385 }}
* {{cite book | last = Williamson | first = Gordon | title = U-boats of the Kaiser's Navy | location = [[Oxford]] | publisher = Osprey | year = 2002 | isbn = 978-1-84176-362-0 | oclc = 48627495 }}
{{Refend}}

{{U-43 class submarines (Austria-Hungary)}}
{{Austro-Hungarian submarine classes}}

{{Good article}}

{{DEFAULTSORT:U-43 Class Submarine (Austria-Hungary)}}
[[Category:Submarine classes]]
[[Category:U-43-class submarines (Austria-Hungary)| ]]